An anti-anxiety medicine
Buspirone
An anti-anxiety medicine that eases generalised anxiety over time, without the dependence risk of benzodiazepines.
What is Buspirone?
Buspirone (Buspar) is a medicine for anxiety, used mainly for generalised anxiety. Unlike benzodiazepines such as diazepam, it is not sedating in the same way and does not cause dependence, but it takes a couple of weeks to work, so it is taken regularly rather than as a one-off 'as needed' calmer.
Education and reference only. This is a plain-language guide to Buspirone — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Buspirone is an anti-anxiety medicine used mainly for generalised anxiety, where worry and tension are present much of the time. It works differently from benzodiazepines: it is not a sedative in the same way, does not cause dependence, and is intended to be taken regularly rather than now and then. In the UK it is a prescription-only medicine.
How it works
Buspirone acts on serotonin (and to a lesser extent dopamine) receptors in the brain, gradually adjusting the brain chemistry involved in anxiety. Because this is a gradual effect, it does not give an immediate calming 'hit' like a benzodiazepine, and the benefit builds over a couple of weeks of regular use. This same mechanism means it does not cause the tolerance and dependence seen with benzodiazepines.
Company & origin
Originated / developed by: Originally Bristol-Myers Squibb (Buspar).
An anxiolytic used in the UK for generalised anxiety, distinct from benzodiazepines.
What it treats
Conditions Buspirone is used for
Practical use
How to take Buspirone
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it regularly as prescribed, not just when you feel anxious, as it needs time to work.
- Take it in a consistent way each day with regard to food, as advised.
- Avoid grapefruit and grapefruit juice, which can raise its levels.
- Give it a couple of weeks of regular use to judge the benefit, and do not expect an instant effect.
- If you miss a dose, take it when you remember unless the next is due soon — do not double up.
Weighing it up
Advantages & disadvantages of Buspirone
Advantages
- Eases generalised anxiety without the dependence and withdrawal seen with benzodiazepines.
- Generally less sedating, so it is less likely to cause heavy daytime drowsiness.
- A useful option for people who need ongoing anxiety treatment.
Disadvantages
- Takes a couple of weeks to work, so it is not for sudden 'as needed' relief.
- Must not be combined with MAOI antidepressants, and grapefruit must be avoided.
- Can still cause dizziness, headache or nausea in some people.
Practical use
Good to know
Buspirone is not suitable for sudden, one-off ('as needed') relief of anxiety because it takes time to work — it needs to be taken regularly for a couple of weeks before you feel the full benefit. Grapefruit and grapefruit juice can raise its levels and should be avoided. It must not be combined with MAOI antidepressants, and care is needed with other medicines that affect serotonin. It is generally less sedating than benzodiazepines, but it can still cause dizziness or drowsiness in some people.
Who should not take it / use with caution
- People taking an MAOI antidepressant, or who stopped one within the past two weeks — a gap is needed when switching between them.
- Used with caution in significant liver or kidney problems, where the dose may need adjusting.
- Anyone who has reacted to it before; check suitability in pregnancy and breastfeeding with a clinician.
Monitoring
- Whether anxiety symptoms improve over the first weeks of regular use.
- Dizziness, headache or nausea, especially when starting.
- Liver and kidney function where these are impaired, as the dose may need adjusting.
Side effects
- Dizziness, headache or light-headedness.
- Nausea, nervousness or feeling excited early on.
- Less commonly, drowsiness; rarely, a serotonin-related reaction if combined with other serotonin medicines.
Key interactions
- MAOI antidepressants must not be combined with it.
- Grapefruit juice and some medicines (such as certain antifungals, antibiotics and the rifampicin antibiotic) change its levels.
- Other serotonin-acting medicines raise the small risk of a serotonin reaction; tell your prescriber about all your medicines.
Available as: Tablets taken by mouth.
Answers
Buspirone: frequently asked questions
How long does buspirone take to work?
It usually takes a couple of weeks of regular use before you feel the full benefit, so it is not suitable for sudden 'as needed' relief of anxiety.
Is buspirone addictive like diazepam?
No — buspirone works differently from benzodiazepines and does not cause the tolerance and dependence associated with medicines like diazepam.
Why must I avoid grapefruit?
Grapefruit and grapefruit juice can raise the level of buspirone in your body, which can increase side effects, so they are best avoided while taking it.
Can I take it just when I feel anxious?
No — buspirone needs to be taken regularly to work, because it builds its effect gradually. It does not give an instant calming effect like a benzodiazepine.
Can I take it with antidepressants?
It must not be combined with MAOI antidepressants, and care is needed with other serotonin-acting medicines, so always tell your prescriber what else you take.
The wider class
About Anxiolytics
Buspirone belongs to the anxiolytics class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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